KNOXVILLE, Tenn. (WATE) – A Knoxville dentist fined and put on probation by the state is being sued by a former assistant who says she was fired for both refusing to participate in misconduct and reporting it to state regulators.

A lawsuit filed in October by former dental assistant Karla Kovalchik claims Nabers reduced her hours on the job and later fired her for refusing to perform dental procedures she was not certified to do and for reporting the misconduct to state regulators.

Dr. Clarence “Buzz” Nabers, who operates two dental practices in Knoxville, was fined $11,000 and had his dental license put on a two-year probationary period in 2018 after an investigation by the Tennessee Board of Dentistry found he made dental assistant perform tasks they were not certified, forged some dental certifications and improperly sterilized equipment.

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Kovalchik’s 2018 complaint to the Tennessee Board of Dentistry led to the investigation and subsequent punishment.

Nabers recently sent patients who visited his office from Sept. 15, 2016, to Sept. 15, 2019, a letter advising them that they may have been exposed to an HIV or HBV infection.

After the only other dentist beside Nabers at the two offices abruptly resigned in 2018, Nabers let dental assistants and hygienists perform duties beyond their professional scope for several months, such as filling cavities or inserting permanent veneers, without being present in the office.

Nabers also admitted to forging several certifications from Arrow Dental Laboratories in Arizona and sending them to dentistry board during an education audit in 2015-2016 and having a dental assistant forge a CPR card with Nabers’ name on it.

Kovalchik’s lawsuit seeks damages of at least $75,000 dollars, pre and post-judgment interest and attorney fees.